Heretofore, visual function testing devices for testing a variety of visual functions have been known. In visual function tests in the ophthalmic treatment, there are many test items. As the test items concerned, there are visual acuity and field tests, a binocular vision test, an eye position test, and the like. The visual function testing devices for the variety of visual function tests as described above are configured according to specifications specialized for test contents of the respective items such as the visual acuity and the visual field, and accordingly, there is not a visual function testing device capable of testing the visual acuity, the visual field and the binocular vision by itself.
As the visual function testing devices, there are known visual function testing devices, each of which is capable of performing two items of the visual function tests as described in Patent Literature 1 and Patent Literature 2, which are described below.
The visual function testing device described in Patent Literature 1 (Japanese Patent No. 3168056) has a function to present visual targets individually to left and right eyes by a dichoptic method using an optical system, a polarization filter, and a red/green filter, and in the same tester, uses such a visual target for the visual acuity test and such a visual target for the binocular vision test. In such a way, the visual function testing device of Patent Literature 1 can perform two visual function tests, which are the visual acuity test and the binocular vision test, by itself.
The visual function testing device described in Patent Literature 2 (Japanese Patent Laid-Open Publication No. 2003-93344) is a device configured in such a manner that a liquid crystal display for the visual acuity test is arranged on a center thereof, and that a light source for the visual field test, which is composed of a large number of LEDs, is arranged on a periphery of the liquid crystal display. In such a way, the visual function testing device of Patent Literature 2 can perform two visual function tests, which are the visual acuity test and the visual field test.